Jospin in a weekend speech did not make a formal announcement of his plans to run against the poll-leading Royal, reports Britain's Independent newspaper. But he accused Royal of trying to hijack the leading opposition party's presidential campaign by appealing to media and the public but not to the party.
In a tearful account to young party supporters, the 69-year-old Jospin said he retired from politics after a humiliating defeat in the first round of the presidential election in April 2002. Since then Jospin has been under pressure from sections of his party to contain Royal's popularity and run in the presidential race next year.
In a statement, Jospin said he had "a vision of the party, a fidelity to authentic left-wing politics and an understanding and respect for grass-roots activism," the report said.
Supporters of Royal see her as a breath of fresh air in French politics, as being the most likely Socialist candidate to win the presidential contest.